---
title: Sega Teradrive
categories:
- Computers
types:
- Home Computer
origins:
- Japan
years:
- '1991'
cpus:
- Intel 80286
params:
  name: Teradrive
  image: /media/museum/photos/sega_teradrive_1.jpg
  company: /companies/sega
  company_name: Sega
  specs:
  - label: NAME
    value: Teradrive
  - label: MANUFACTURER
    value: Sega
  - label: TYPE
    value: Home Computer
  - label: ORIGIN
    value: Japan
  - label: YEAR
    value: May 1991
  - label: KEYBOARD
    value: Full-stroke professional keyboard. 106 keys with function keys, cursor keys and numeric keypad
  - label: CPU
    value: Intel 80286 + Motorola MC68000 + Zilog Z80A (used for sound system)
  - label: SPEED
    value: 10 MHz (80286) / 10 MHz (68000) / 3.58 MHz (Z80A)
  - label: CO-PROCESSOR
    value: Megadrive customchips (?)
  - label: RAM
    value: 2.5 MB (512 KB onboard + two 1 MB SIMM RAMs)
  - label: VRAM
    value: 256 KB
  - label: ROM
    value: 128 KB
  - label: TEXT MODES
    value: 40 or 80 chars x 25 lines
  - label: GRAPHIC MODES
    value: 320 x 244 (Megadrive VDP Mode) / 320 x 200 (MCGA) / 640 x 480 (VGA)
  - label: COLORS
    value: 64 among 512 (Megadrive Mode) / 256 among 262144 (S/VGA Modes)
  - label: SOUND
    value: FM Sound / PCM Sound (Megadrive) - Beeper (PC)
  - label: SIZE / WEIGHT
    value: 36 (W) x 33.4 (D) x 8 (H) cm / 5.6 to 6.2 Kg according to versions
  - label: I/O PORTS
    value: RGB analog vide output, composite video output, 1 ISA slot, mouse, keyboard, serial (2) & parallel (1) ports, headphone output, 2 joystick ports
  - label: BUILT IN MEDIA
    value: 3.5'' disk-drive, 30 MB hard drive
  - label: OS
    value: DOS/V
  - label: POWER SUPPLY
    value: Built-in PSU
  - label: PRICE
    value: 148,000¥ (Mod.1), 188,000 ¥ (Mod.2), 248,000 (Mod.3) (Japan, 1991)
  tabs:
  - photos
  - adverts
  - connectors
  - software
  - links
  - videos
  photos:
  - title: MAIN UNIT
    subtitle: ''
    text: ''
    image: /media/museum/photos/sega_teradrive_main-unit.jpg
  adverts:
  - title: JAPANESE ADVERT (1991)
    subtitle: ''
    text: This japanese advert indicates that there were at least 3 different models sold...
    image: /media/museum/pubs/sega_teradrive_jap-pub_1.jpg
  connectors:
  - title: SEGA TERADRIVE
    subtitle: RGB monitor pinout
    text: |-
      1 - Red\
      2 - Green\
      3 - Blue\
      4 - Horizontal/Composite Sync\
      5 - Vertical Sync\
      6 - Red Shield\
      7 - Green Shield\
      8 - Blue Shield\
      9 - Ground
    image: /media/museum/connectors/sega_teradrive_videou-output.jpg
  screenshots:
  - title: BOOT SCREEN
    subtitle: ''
    text: Start-up menu with several options, including file manager, DOS, clock and MegaDrive mode.
    image: /media/museum/software/sega_teradrive_boot.jpg
  links:
  - title: Assembler - Teradrive page
    url: http://assembler.roarvgm.com/teradrive/teradrive.html
    text: Some pictures & info here
  - title: Mic's homepage
    url: http://www1.odn.ne.jp/~caa09810/old_pc/pc_tera.htm
    text: Nice small japanese description
  - title: nfg.2y.net - Teradrive page
    url: http://nfg.2y.net/games/teradrive/
    text: Another interesting page in English
  - title: Qwerters Clinic
    url: http://www.ai.wakwak.com/~ex4/kb/main_sega_teradrive.htm
    text: Nice japanese page dedicated on the Teradrive's keyboard (!)
  videos:
  - title: Sega Teradrive - Japanese advert
    url: http://video.google.com/googleplayer.swf?docId=-4391346534753818861&hl=fr
    text: 'Length: 14 s'
  comments:
  - author: Tof
    date: Saturday 22nd June 2019
    text: |-
      Hello\
      Amstrad sold this type of computer too (in France for sure, rest of Europe I don''t know): Amstrad Mega-PC
  - author: Linkman (TV commercial for Sega Terradrive)
    date: Friday 3rd February 2006
    text: |-
      You wanna see tv commercial of this sega ?\
      See this\
      http://www.youtube.com/?v=mGYN_H_kAD0
  - author: Trevor H. (USA)
    date: Tuesday 30th April 2002
    text: It is said that this is a very reliable computer, I also remember hearing that it was pretty popular in Japan, it was never released in the US, it could use any accesories developed for the PC XT because it used the ISA standard, it ran a version of Windows, possibly 3.1, and MS-DOS
  - author: dakota (kop)
    date: Sunday 28th April 2002
    text: are you going to sell it
  oc_id: 518
  source:
    url: https://web.archive.org/web/20230326085701/http://www.old-computers.com/museum/computer.asp?c=518
    date: '2023-03-26'
---

What a strange computer ! It was built by IBM (like the [Atari Jaguar](/museum/atari-jaguar/) few years later) in Japan for Sega, and was sold only there.

It is an [IBM PC AT](/museum/ibm-pc-at/) compatible system mixed with a Sega Megadrive (Genesis) console. On the front panel, one can find a Megadrive cartridge slot, two joystick connectors, a reset button, a MD/PC switch, a volume slider, a headphone output, a power button, keyboard/mouse connectors (PS/2) and one 3.5'' disk drive.

Three models were released, a low-end **Model 1**, with 640k RAM and no HD, a **Model 2** with two floppies and no HD and 1MB RAM, and the high-end **Model 3**, with one floppy, 2.5MB RAM and a 30MB drive. All three shipped with the same software and accessories.

Amstrad made later a similar computer called **MegaPC**.